描述 Description

The 8T49N1012 has one fractional-feedback PLL that can be used

for frequency synthesis. It is equipped with two integer and eight

fractional output dividers, allowing the generation of up to ten different

output frequencies, ranging from 8kHz to 1GHz. Eight of these

frequencies are completely independent of each other and the inputs.

Two more are related frequencies. The twelve outputs may select

among LVPECL, LVDS, HSCL or LVCMOS output levels.

This functionality makes it ideal to be used in any frequency synthesis

application, including 1G, 10G, 40G and 100G Synchronous Ethernet,

OTN, and SONET/SDH, including ITU-T G.709 (2009) FEC rates.

The device supports Output Enable inputs and Lock and LOS status

outputs.

The device is programmable through an I2C interface. It also supports

I

2C master capability to allow the register configuration to be read

from an external EEPROM.

特性 Features

? <350fs RMS typical jitter (including spurs), @122.88MHz (12kHz

to 20MHz)

? Operating modes: locked to input signal and free-run

? Operates from a 10MHz to 40MHz fundamental-mode crystal

? Accepts one LVPECL, LVDS, LVHSTL, HCSL or LVCMOS input

clock

? Accepts frequencies ranging from 10MHz up to 600MHz

? Clock input monitoring

? Generates 12 LVPECL / LVDS / HSCL or 24 LVCMOS output

clocks

? Output frequencies ranging from 8kHz up to 1.0GHz (Q[8:11],

Differential)

? Output frequencies ranging from 8kHz to 250MHz (LVCMOS)

? Two Output Enable control inputs

? Lock and Loss-of-Signal status outputs

? Programmable output de-skew adjustments in steps as small as

16ps

? Register programmable through I2C or via external I2C EEPROM

? Bypass clock paths and Reference Output for system tests

? Power supply modes:

VCC / VCCA / VCCO

3.3V / 3.3V / 3.3V

3.3V / 3.3V / 2.5V

3.3V / 3.3V / 1.8V (LVCMOS)

2.5V / 2.5V / 3.3V

2.5V / 2.5V / 2.5V

2.5V / 2.5V / 1.8V (LVCMOS)

? -40°C to 85°C ambient operating temperature

? Package: 72QFN, lead-free RoHs (6)